THE DISTRIBUTION OF SPHAGNUM SPECIES ALONG AN ELEVATIONAL GRADIENT INTHE SOUTHERN ALPS (ITALY)

Response curves for 16 species of Sphagnum along an elevational gradie nt were obtained using data from 116 mire sites in South Tyrol (Italy) . Most of the species investigated exhibit unimodal curves along the g radient, usually peaking at low elevations. Only three species have bi modal curves. The shape of the curves is mainly determined by the indi rect effects climate exerts on the altitudinal distribution of mire ty pes and microhabitats rather than by a direct response of species to c limatic factors.